Tnt why explosive

Andrews Dr. Kevin M. Composition B , TNT exudation in projectiles, bombs, and rockets has been a recurring problem since the early s. TNT exudate typically has an oily appearance and dries to a somewhat black colour. The formation of exudate is associated with TNT impurities. Exudate by itself appears to be no more sensitive than TNT. However, if mixed with sand or grit, it can be very sensitive to impact or friction.

Munitions that have TNT exudate in any part of the munition except were the design allows, should not be considered as safe and suitable for service. TNT exudate is formed due to the presence of DNT, and other impurities within TNT, combined with the high temperatures that can be experienced in the service environment of munitions filled with TNT containing explosive compositions.

First, it contains the elements carbon, oxygen and nitrogen, which means that when the material burns it produces highly stable substances CO, CO 2 and N 2 with strong bonds, so releasing a great deal of energy.

This is a common feature of most explosives; they invariably consist of many nitrogen or oxygen containing groups usually in the form of 2, 3 or more nitro-groups , attached to a small, constricted organic backbone. However, explosives like TNT, actually have less potential energy than gasoline, but it is the high velocity at which this energy is released that produces the blast pressure. This very high speed reaction is called a detonation.

The second fact that makes TNT explosive is that it is chemically unstable - the nitro groups are so closely packed that they experience a great deal of strain and hindrance to movement from their neighbouring groups. Thus it doesn't take much of an initiating force to break some of the strained bonds, and the molecule then flies apart. Typically 1 gram of TNT produces about 1 litre of gas, which is a fold increase in volume. This expanding hot gas can be used to propel a projectile, such as a bullet from a gun, or for demolition purposes.

There are a number of advantages that TNT has for ammunition manufacturers. Secondly, it is not too unstable - allowing it to be handled reasonably safely during manufacture and operation. TNT will not spontaneously explode, and in fact can be treated quite roughly. In order to initiate the explosion, TNT must first be detonated using a pressure wave from another, more easily induced explosion from another explosive called a detonator.

One such detonator is lead azide , Pb N 3 2 , which explodes when struck or if an electric discharge is passed through it.